Method of Operating a Wireless Electrical Energy Transmission Base

ABSTRACT

A wireless electrical energy transmission system is provided. The system comprises a wireless transmission base configured to wirelessly transmit electrical energy or data via near field magnetic coupling to a receiving antenna configured within an electronic device. The wireless electrical energy transmission system is configured with at least one transmitting antenna and a transmitting electrical circuit positioned within the transmission base. The transmission base is configured so that at least one electronic device can be wirelessly electrically charged or powered by positioning the at least one device external and adjacent to the transmission base.

RELATED APPLICATION

This application claims priority to U.S. Provisional Application No.62/458,261, filed on Feb. 13, 2017, the disclosure of which is entirelyincorporated herein by reference.

TECHNICAL FIELD

The present disclosure generally relates to the wireless transmission ofelectrical energy and data. More specifically, this application relatesto various embodiments which enable the transmission of wirelesselectrical energy by near-field magnetic coupling.

BACKGROUND

Near field magnetic coupling (NFMC) is a commonly employed technique towirelessly transfer electrical energy. The electrical energy may be usedto directly power a device, charge a battery or both.

In near field magnetic coupling (NFMC) an oscillating magnetic fieldgenerated by a transmitting antenna passes through a receiving antennathat is spaced from the transmitting antenna, thereby creating analternating electrical current that is received by the receivingantenna.

However, the oscillating magnetic field radiates in multiple directionsand at a relatively short distance from the transmitting antenna. Thus,electronic devices, such as a cellular phone, that are charged withprior art charging systems that utilize NFMC are required to bepositioned directly in physical contact with the surface of the priorart transmitting base, such as a charging mat, that houses a prior artantenna. Because the electronic device is required to be in physicalcontact with the prior art charging base, the number of electronicdevices that can be electrically charged is limited to one device.Furthermore, since the electronic device is required to be in physicalcontact with the prior art charging base, the device cannot be usedwhile it is being electrically charged.

In contrast to the prior art, the present invention provides a wirelesselectrical power transmitting system that enables multiple electronicdevices to be simultaneously electrically charged or powered.Furthermore, in contrast to the prior art, the wireless electrical powertransmitting system enables multiple electronic devices to beelectrically charged or powered by positioned one or more devices at adistance away from the wireless transmitting base of the presentinvention. Therefore, not only can multiple devices be electricallycharged or powered simultaneously, they can also be utilized by a user.

SUMMARY

The present disclosure relates to the transfer of wireless electricalenergy to and from electronic devices that are configured to utilizewirelessly transmitted electrical energy. Such electronic devices mayinclude, but are not limited to, consumer electronics, medical devices,and devices used in industrial and military applications.

In one or more embodiments, a wireless electrical power transmissionsystem is provided comprising an electrical power transmission base anda wireless electrical power receiving antenna that is incorporatablewithin an electronic device. In one or more embodiments, the electricalpower transmission base comprises at least one wireless electrical powertransmitting antenna that is housed therewithin. In one or moreembodiments the wireless electrical power transmitting antenna isconfigured with one or more magnetic field shielding embodiments thatincrease the magnitude of the magnetic field that emanates from theantenna. In one or more embodiments the wireless electrical powertransmitting antenna is configured with one or more magnetic fieldshielding embodiments that control the direction in which the magneticfield emanates from the antenna. Furthermore, the transmitting and/orthe receiving antenna is configured with one or more embodiments thatincrease the efficiency, reduces form factor and minimizes cost in whichelectrical energy and/or data is wirelessly transmitted. As a result,the present invention provides a wireless electrical energy transmissionsystem comprising a wireless electrical energy transmitting base thatenables wireless electrical charging and powering of electronic devicesthat are positioned at a distance from the wireless transmission base.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an embodiment of an electronic device positioneddirectly on a surface of a prior art wireless transmitting base.

FIG. 2 shows an embodiment of multiple electronic devices being chargedby positioning them adjacent to the wireless electrical transmissionbase of the present invention.

FIGS. 3 and 4 illustrate embodiments of a block diagram of an electricalcircuit configured to condition electrical energy to be transmittedwirelessly.

FIG. 4A is an electrical schematic diagram of an embodiment of atransmitting antenna selector sub-circuit.

FIG. 5 illustrates an embodiment of a transmitting antenna positionedwithin the wireless electrical transmission base of the presentinvention.

FIG. 5A illustrates a cross-sectional view of a transmitting antennapositioned within the wireless electrical transmission base of thepresent invention.

FIGS. 6-8 illustrate embodiments of configurations of transmittingantennas that may be positioned within the wireless electricaltransmission base of the present invention.

FIGS. 9 and 9A illustrate embodiments of a transmitting antennapositioned along an interior surface of the housing and the wirelesselectrical transmission base of the present invention.

FIGS. 10 and 11 illustrate embodiments of configurations of atransmitting antenna positioned along an interior surface of the housingand the wireless electrical transmission base of the present invention.

FIG. 12 illustrates an embodiment showing two transmitting antennaspositioned within the wireless electrical transmission base in relationto two electronic devices positioned external and adjacent to the base.

FIG. 12A is a cross-sectional view of the two transmitting antennaspositioned within the wireless electrical transmission base asillustrated in the embodiment of FIG. 12.

FIG. 13 shows an embodiment of a block diagram of an electrical circuitconfigured to condition electrical energy to be transmitted wirelesslycomprising a repeater antenna.

FIG. 14 illustrates an embodiment showing two repeater antennas inrelationship to a transmitting antenna positioned within the wirelesselectrical transmission base and in relation to two electronic devicespositioned external and adjacent to the base.

FIGS. 15 and 16 illustrate embodiments of a flexible transmittingantenna that may be incorporated within the wireless electrical energytransmission system of the present invention.

FIG. 17 is a graph that illustrates an embodiment of the direction andmagnitude of a magnetic field emanating from a transmitting antenna as afunction of distance.

FIG. 18 is a cross-sectional view of an embodiment of a construction ofa transmitting or receiving antenna that may be used within the wirelesstransmission system of the present invention.

FIG. 19 is a cross-sectional view of an embodiment of a transmittingantenna positioned within the wireless electrical transmission base.

FIG. 19A is a cross-sectional view of an embodiment of a transmittingantenna positioned within the wireless electrical transmission base inrelation to a receiving antenna positioned within an electronic devicepositioned external of the base.

FIG. 20 is a cross-sectional view of an embodiment of a transmittingantenna positioned within the wireless electrical transmission base.

FIG. 21 illustrates an embodiment of a transmitting or receiving antennathat may be incorporated within the wireless transmission system of thepresent invention.

FIG. 21A is a cross-sectional view of the transmitting or receivingantenna shown in FIG. 20.

FIG. 22 is a cross-sectional view of an embodiment of a transmitting orreceiving antenna that may be incorporated within the wirelesstransmission system of the present invention.

FIGS. 23 and 24 show embodiments of magnetic field shielding materialthat may be used with a transmitting or receiving antenna of thewireless transmission system of the present invention.

FIG. 25A illustrates an embodiment of a transmitting or receivingantenna that may be used with the wireless transmission system of thepresent invention.

FIG. 25B illustrates an embodiment of a transmitting or receivingantenna comprising magnetic field shielding material that may be usedwith the wireless transmission system of the present invention.

FIG. 25C illustrates an embodiment of a transmitting or receivingantenna comprising magnetic field shielding material and a layer of aconductive material that may be used with the wireless transmissionsystem of the present invention.

FIG. 26 shows an embodiment of a wireless electrical energy transmissiontest configuration comprising a receiving antenna and a transmittingantenna.

FIG. 27 illustrates an embodiment of a parallel plate capacitor and aninterdigitated capacitor that may be incorporated within either or botha transmitting or receiving antenna.

FIGS. 28A-28C illustrate embodiments of configurations of interdigitatedcapacitors that may be incorporated within either or both a transmittingor receiving antenna.

FIG. 29 illustrates a cross-sectional view of an embodiment of atransmitting or receiving antenna having an interdigitated capacitor.

FIGS. 30A, 30B, and 30C are electrical schematic diagrams of embodimentsof a transmitting or a receiving antenna comprising a lumped circuitelements.

FIGS. 31 and 32 are graphs that illustrate the efficiency of twoembodiments of a transmitting antenna as a function of the imaginary andreal impedances of an electrical load in ohms.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth byway of examples in order to provide a thorough understanding of therelevant teachings. However, it should be apparent to those skilled inthe art that the present teachings may be practiced without suchdetails. In other instances, well known methods, procedures, components,and/or circuitry have been described at a relatively high-level, withoutdetail, in order to avoid unnecessarily obscuring aspects of the presentteachings.

The various embodiments illustrated in the present disclosure providefor the wireless transfer of electrical energy and/or data. Morespecifically, the various embodiments of the present disclosure providefor the wireless transfer of electrical energy and/or data via nearfield magnetic coupling between a transmitting base and a receivingantenna positioned within an electronic device.

Now turning to the figures, FIG. 1 illustrates an example of a prior artwireless electrical charging device 10, such as a charging mat. Asshown, the prior art wireless charging device 10 is configured such thatan electronic device 12 intended to be charged, must be placed inphysical contact with a surface of the charging device. This is becauseof a number of factors. First, the wireless signal emitted by prior artcharging devices 10 is generally too weak to travel any significantdistances. Second, the respective prior art transmitting and receivingantennas are of poor efficiency such that a large portion of the signalis lost and not received by the device. Thus, a result, prior artwireless charging devices 10, such as the example shown in FIG. 1,require that an electronic device 12 intended to be charged bepositioned as close to the charging device 10 as possible, hence theneed to position the electronic device 12 directly on an exteriorsurface of the prior art wireless charging device 10.

Since prior art wireless electrical charging devices 10 require physicalcontact with an electronic device 12 to enable charging or powering ofthe electronic device 12, the number of devices able to besimultaneously charged or powered is significantly limited. In manycases, the relatively weak signal and relatively small surface area ofprior art wireless charging devices 10 limit the number of electronicdevices 12 being charged or powered to one. Furthermore, requiring theelectronic device 12 be in physical contact with the prior art wirelesscharging device 10 limits the use of the electronic device 12 whilebeing charged. For example, in many cases, one cannot use an electronicdevice 12 while it is being charged by a prior art wireless chargingdevice 10 since it is in physical contact with the charging device whichthus does not allow the electronic device 12 to be held and manipulated.

As will be described in detail, the present invention in contrast toprior art wireless charging devices 10, addresses these problems byproviding a wireless electrical energy transmitting system 14 comprisinga wireless transmitting base 16 that allows for multiple electronicdevices to be electrically charged or powered wirelessly simultaneously.Furthermore, unlike the prior art, the transmitting base 16 of thepresent invention allows for wireless electrical charging and/orelectrical powering of at least one electronic device 12 that ispositioned at a distance away from the transmitting base 16. In contrastto prior art wireless charging devices 10, the wireless electricalenergy transmitting system 14 of the present invention utilizes nearfield magnetic coupling (NFMC) in which magnetic fields 15 (FIG. 12)that emanate from within the transmitting base 16 are magnified and areable to be steered to emanate at a specific direction or directions. Thewireless transmitting base 16 of the present invention is furtherconfigured so that electric fields are suppressed. As a result,transmitted magnetic fields travel further distances thereby allowingfor multiple devices to be charged or powered at longer distances fromthe wireless transmitting base 16.

In this application, the inventive concepts particularly pertain tonear-field magnetic coupling (NFMC). NFMC enables the transfer ofelectrical energy and/or data wirelessly through magnetic inductionbetween a transmitting antenna 18 and a corresponding receiving antenna20. The NFMC standard, based on near-field communication interface andprotocol modes, is defined by ISO/IEC standard 18092. Furthermore, asdefined herein “inductive charging” is a wireless charging techniquethat utilizes an alternating electromagnetic field to transferelectrical energy between two antennas. “Resonant inductive coupling” isdefined herein as the near field wireless transmission of electricalenergy between two magnetically coupled coils that are tuned to resonateat a similar frequency. As defined herein, “mutual inductance” is theproduction of an electromotive force in a circuit by a change in currentin a second circuit magnetically coupled to the first circuit.

As defined herein a “shielding material” is a material that captures amagnetic field. Examples of shielding material include, but are notlimited to ferrite materials such as zinc comprising ferrite materialssuch as manganese-zinc, nickel-zinc, copper-zinc, magnesium-zinc, andcombinations thereof. A shielding material thus may be used to direct amagnetic field to or away from an object, such as a parasitic metal,depending on the position of the shielding material within or nearby anelectrical circuit. Furthermore, a shielding material can be used tomodify the shape and directionality of a magnetic field. As definedherein a parasitic material, such as a parasitic metal, is a materialthat induces eddy current losses in the inductor antenna. This istypically characterized by a decrease in inductance and an increase inresistance of the antenna, i.e., a decrease in the quality factor. An“antenna” is defined herein as a structure that wirelessly receives ortransmits electrical energy or data. An antenna comprises a resonatorthat may comprise an inductor coil or a structure of alternatingelectrical conductors and electrical insulators. Inductor coils arepreferably composed of an electrically conductive material such as awire, which may include, but is not limited to, a conductive trace, afilar, a filament, a wire, or combinations thereof.

It is noted that throughout this specification the terms, “wire”,“trace”, “filament” and “filar” may be used interchangeably. As definedherein, the word “wire” is a length of electrically conductive materialthat may either be of a two dimensional conductive line or track thatmay extend along a surface or alternatively, a wire may be of a threedimensional conductive line or track that is contactable to a surface. Awire may comprise a trace, a filar, a filament or combinations thereof.These elements may be a single element or a multitude of elements suchas a multifilar element or a multifilament element. Further, themultitude of wires, traces, filars, and filaments may be woven, twistedor coiled together such as in a cable form. The wire as defined hereinmay comprise a bare metallic surface or alternatively, may comprise alayer of electrically insulating material, such as a dielectric materialthat contacts and surrounds the metallic surface of the wire. A “trace”is an electrically conductive line or track that may extend along asurface of a substrate. The trace may be of a two dimensional line thatmay extend along a surface or alternatively, the trace may be of a threedimensional conductive line that is contactable to a surface. A “filar”is an electrically conductive line or track that extends along a surfaceof a substrate. A filar may be of a two dimensional line that may extendalong a surface or alternatively, the filar may be a three dimensionalconductive line that is contactable to a surface. A “filament” is anelectrically conductive thread or threadlike structure that iscontactable to a surface. “Operating frequency” is defined as thefrequency at which the receiving and transmitting antennas operate.“Self-resonating frequency” is the frequency at which the resonator ofthe transmitting or receiving antenna resonates.

In one or more embodiments, the wireless transmitting base 16 is acomponent of the wireless electrical energy transmitting system 14. Theelectrical energy transmitting system 14 comprises the transmitting base16 and a receiving antenna 20 configured to receive the wirelesslytransmitted electrical energy. In one or more embodiments, the wirelesselectrical energy transmitting system 14 may comprise at least oneelectronic device 12 having the receiving antenna 20 configured toreceive wireless electrical energy and/or data transmitted from the base16. In one or more embodiments, the at least one electronic device 12acts as a receiving device that receives and conditions the wirelesslytransmitted electrical energy so that it can be used to electricallypower the device or store the wirelessly received electrical energy. Inone or more embodiments, the at least one electronic device 12configured to receive the wirelessly transmitted electrical energy mayalso comprise an electrical energy storage device (not shown) such as anelectrochemical cell or battery pack configured to store the receivedwirelessly transmitted electrical energy.

In one or more embodiments, the wireless transmitting base 16 comprisesat least one transmitting antenna 18 that is electrically connected to atransmitting electronic circuit 22 configured to condition electricalenergy to be wirelessly transmitted by the transmitting antenna 18. Inone or more embodiments, the at least one transmitting antenna 18 andthe transmitting electronic circuit 22 reside within a housing 24 of thewireless transmitting base 16. In one or more embodiments the electronicdevice 12 comprises the receiving antenna 20 and a receiving electricalcircuit (not shown) configured to condition the received wirelesselectrical energy to be used to either electrically power the electronicdevice 12 and/or store the wireless electrical energy within anelectrical energy storage device within the electronic device 12.

FIG. 2 illustrates an embodiment of the wireless electrical energytransmitting system 14 of the present invention. As shown, the wirelesselectrical transmitting system 14 comprises the wireless transmittingbase 16 and at least one electronic device 12 configured to receive thewireless electrical energy. As illustrated, in an embodiment, thetransmitting base 16 has a length 26 that extends from a base proximalend 28 to a base distal end 30. In one or more embodiments, the baseproximal end 28 may be positioned directly adjacent or in contact with asupporting structure such as a table, desk or floor.

In one or more embodiments, the transmitting base housing 24 comprisesan enclosure having a sidewall within which the at least onetransmitting antenna 18 and the transmitting electronic circuit 22 arepositioned. Alternatively, the transmitting electronic circuit 22 may bepositioned external of the base housing 24.

In addition, in one or more embodiments, the transmitting base 16 may beconfigured with at least one repeater 32 (FIG. 13) positionedtherewithin. As defined herein a repeater is an antenna that isconfigured to relay magnetic fields emanating between a transmittingantenna 18 and a receiving antenna 20 or another repeater 32, thus therepeater 32 is configured to relay electrical energy via NMFC frombetween a transmitting antenna 18 and a receiving antenna 20. In one ormore embodiments, the repeater 32 comprises an inductor coil capable ofresonating at a frequency that is about the same as the resonatingfrequency of the transmitting and receiving antennas 18, 20.

As shown in the embodiment, illustrated in FIG. 2, the transmitting basehousing 24 comprises six sidewalls. As shown, the housing 24 comprises abottom sidewall 34 positioned at the base proximal end 28, a topsidewall 36 opposed from the bottom sidewall 34 positioned at the basedistal end 30, opposed front and back sidewalls 38, 40 orientedperpendicular to the bottom and top sidewalls 34, 36 and opposed leftand right sidewalls 42, 44 that join and meet the front and backsidewalls 38, 40 oriented perpendicular to the bottom and top sidewalls34, 36. In one or more embodiments the transmitting base 16 comprises abase width 46 that extends between the left and right sidewalls 42, 44and a base depth 48 oriented perpendicular to the width 46 that extendsbetween the front and back sidewalls 38, 40. In one or more embodiments,the transmitting base length 26, width 46 and depth 48 are dependent onthe operating frequency, distance between the transmitting and receivingantennas 18, 20, the amount of electrical power being wirelesslytransmitted and any electrically conductive surfaces that may bepositioned in the vicinity of the transmitting base 16.

In one or more embodiments, the physical dimensions of the transmitterbase 16 may affect electrical performance as the dimensions of thetransmitting base 16 may dictate the dimensions and/or positioning ofthe transmitting antenna 18 therewithin. For example, given acylindrical shaped transmitting base having a diameter, in order towirelessly transmit electrical energy to the same location, away fromthe base 16, the transmitting antenna 18 therewithin must be constructedhaving an increased inductance in comparison to a transmitting antennapositioned within a cylindrically shaped transmitting base having alarger diameter. In one or more embodiments, the inductance of atransmitting antenna 18 constructed having a transmitting inductor coil50 may be increased by constructing the transmitting inductor coil 50with an increased number of coil turns. Thus, in this example, byincreasing the number of coil turns of the transmitting coil 50 and/ordecreasing the size of the transmitting antenna 18 such that it fitswithin a transmitting base 16 having a decreased diameter or volume, theequivalent series resistance (ESR) of the transmitting antenna 18generally increases due to the increased proximity effect due to theincreased number of coils and reduced spacing between coil turns. Thus,as a result, the efficiency of the wireless transmission of theelectrical energy and/or data from the transmitting antenna 18decreases. Furthermore, in general, as the diameter or width 46 anddepth 48 of the transmitting base 16 decreases, the distance away fromthe base 16 at which electrical energy and/or data can be transmitteddecreases as there is a maximum inductance with which the transmittingantenna 18 can be constructed to maintain transmitting distance.Similarly, as the length 26 of the transmitting base 16 decreases theinductance of the transmitting antenna 18 should be increased tomaintain wireless transmission distance. However, the extent to whichthe inductance of the transmitting antenna 18 can be increased isgenerally limited by the antenna's self-resonant frequency. Therefore,decreasing the length 26 of the wireless transmitting base 16 couldreduce the wireless transmission distance if the length 26 of the base16 is reduced more than can be compensated by increasing the inductanceof the transmitting antenna 18.

In one or more embodiments the transmitting base sidewalls have athickness 52 (FIG. 12A) that extends between an interior sidewallsurface 54 and an exterior sidewall surface 56. In one or moreembodiments, the interior sidewall surfaces 54 face toward the interiorof the wireless transmitting base housing 24. In one or moreembodiments, the sidewall thickness 52 may affect the coupling betweenthe transmitting and receiving antennas 18, 20. In general, coupling andefficiency between the transmitting and receiving antennas 18, 20 isincreased by constructing the housing sidewalls as thin as possible. Inone or more embodiments, the wireless transmitting base housing 24 canbe constructed having a multitude of sidewall thicknesses. In one ormore embodiments, the sidewall thickness 52 may range from about 0.1 mmto about 5 mm. As shown, multiple electronic devices 12, configured toreceive wireless electrical energy such as a cellular phone and a watchare positioned about the wireless transmitting base housing 24. However,it is noted that the electronic device 12 or multiple electronic devices12 may include any electronic device configured to receive wirelesselectrical energy emanating from the wireless transmitting base 16.Examples of other such devices include but are limited to a computer, aradio, or a wearable electronic device. In one or more embodiments, thewireless transmitting base 16 of the present application is configuredto wirelessly transmit electrical power ranging from about 1 mW to about500 W over a transmission distance ranging from about 0 mm to about 50mm.

It is further noted that while the embodiment of the wirelesstransmitting base 16 as illustrated in FIG. 2, is configured in arectangular cube shape, the wireless transmitting base 16 of the presentinvention may comprise a variety of non-liming three-dimensional shapesand configurations among which may include, but are not limited to, atriangular pyramid, a cylinder, or other three dimensional polygonshaped configuration. An example of such a cylindrical housingconfiguration includes a length 26 ranging from about 50 mm to about 100mm and a diameter 58 that ranges from about 50 mm to about 100 mm. Inaddition, in one or more embodiments, the transmitting base housing 24may comprise an electrically non-conductive material. Examples of suchmaterials may include a polymer, a ceramic, a glass or combinationsthereof.

FIGS. 3 and 4 are electrical block diagrams that illustrate embodimentsof the transmitting electronic circuit 22 that may be housed within thehousing 24 of the transmitting base 16. Alternatively, the transmittingelectrical circuit 22 may reside external of the transmitting base 16.As shown, a power supply sub-circuit 60 is electrically connected to acommunication and control sub-circuit 62. In one or more embodiments,the power supply sub-circuit 60 may be electrically connectable to anexternal power supply 61 (FIG. 13) such as an electrical wall outlet(not shown). In one or more embodiments, the communication and controlsub-circuit 62 comprises a master control unit that controls theoperation of the transmitting base 16 and transmission of wirelesselectrical energy. As shown in FIG. 3, the communication and controlsub-circuit 62 is electrically connected to at least one inverter 64that converts direct current electrical energy to alternating currentelectrical energy. The at least one inverter 64 is electricallyconnected to the transmitting antenna 18 that resides within the housing24 of the wireless transmitting base 16. As shown in FIG. 3, thetransmitting electronic circuit 22 comprises three inverters 64, eachinverter 64 is electrically connected to a transmitting antenna 18comprising a transmitting inductor coil 50 within the housing 24 of thetransmitting base 16.

Alternatively, as shown in FIG. 4, the transmitting circuit 22 maycomprise a transmitting antenna selector sub-circuit 66. In one or moreembodiments, the transmitting antenna selector sub-circuit 66illustrated in FIG. 4A is configured with an integrated circuitrectifier 68 comprising field effect transistors Q₁-Q₄ and capacitor C₁.In addition, the transmitting antenna selector sub-circuit 66 compriseselectrical resistors R₁-R₅, capacitors C₂-C₃, inductors L₁-L₃ and fieldeffect transistors Q₅-Q₈. In an embodiment, as shown in FIGS. 4 and 4A,the transmitting antenna selector sub-circuit 66 is configured to selectat least one transmitting antenna 18 that resides within the housing 24of the transmitting base 16. In an embodiment, the transmitting antennaselector sub-circuit 66 dynamically communicates with the communicationand control sub-circuit 62 to actively select which transmitting antennaor antennas 18 are used to wirelessly transmit electrical energy. In oneor more embodiments, field effect transistors Q₅-Q₈ are configured toimplement the antenna selector sub-circuit 66 and are set by a pair ofvoltage dividers.

As shown in the block diagram of FIG. 4, the power supply sub-circuit 60is electrically connected to the inverter 64 and the communication andcontrol sub-circuit 62. In one or more embodiments, the power supplysub-circuit 60 may be electrically connectable to an external electricalpower supply 61 (FIG. 13), such as an electrical outlet (not shown). Asin the block diagram of FIG. 3, the inverter 64 converts electricalpower from direct electrical current to alternating electrical current.The communication and control sub-circuit 62 comprising a master controlunit, controls the operation of the transmitting base 16 and flow of thetransmitted wireless electrical energy.

FIG. 5 illustrates an embodiment of a transmitting antenna 18 positionedwithin the housing 24 of the transmitting base 16. As shown, thetransmitting antenna 18 comprises a transmitting inductor coil 50positioned in contact with a magnetic field shielding material 70 suchas a ferrite material. In one or more embodiments, the transmittinginductor coil 50 may be positioned adjacent to the magnetic fieldshielding material 70. In one or more embodiments a transmitting antennathickness 72 extends between opposing exterior surfaces of thetransmitting inductor coil 50 and shielding material 70. In anembodiment, as shown in FIG. 5, the transmitting antenna 18 is of arectangular shape having a transmitting antenna outer perimeter 74defined by an outer edge 76. An opening 78 extends through the thickness72 of the transmitting antenna 18 within the outer perimeter 74. Theopening 78 thus defines a transmitting antenna inner perimeter 80. Awidth 82 extends between the antenna inner perimeter 80 and the antennaouter perimeter 74. In one or more embodiments, the transmitting antenna18 is positioned within the housing 24 of the transmitting base 16 suchthat the outer edge 76 along the antenna outer perimeter 74 is inphysical contact with an interior surface 54 of the transmitting basehousing 24.

In one or more embodiments, the transmitting antenna 18 or repeater 32may be positioned having a gap 84 that extends between the transmittingantenna 18 or repeater 32 and the proximal end 28 of the transmittingbase 16. As defined herein, the gap 84 extends from the interior surface54 of the bottom sidewall 34 at the proximal end 28 of the transmittingbase 16 to a surface of the transmitting antenna 18 or repeater 32 thatfaces the transmitting base proximal end 28. In an embodiment, the gap84 may range from about 0 cm such that the transmitting antenna 18 orrepeater 32 is in physical contact with the interior surface 54 of thebottom sidewall 34 at the proximal base end 28 to about 10 cm distal ofthe bottom sidewall 34. Alternatively, the gap 84 may range from about 0percent of the base length 26, such that the transmitting antenna 18 orrepeater 32 is in physical contact with the interior surface 54 of thebottom sidewall 34 at the base proximal end 28 to about 90 percent ofthe base length 26. Furthermore, at least one transmitting antenna 18 orrepeater 32 may be positioned within the transmitting base housing 24such that the at least one transmitting antenna 18 and repeater 32 arein physical contact with the interior surface 54 of the top sidewall 36at the base distal end 30. In one or more embodiments modifying the gap84 typically changes the distance between the transmitting and receivingantennas 18, 20. Generally, as the gap 84 increases, the range withinwhich electrical energy is able to be transmitted is increased. Forexample, in an embodiment the transmitting base 16 may be constructedwith a transmitting antenna 18 with a gap 84 of about 45 mm, thus therange within which electrical energy is able to be wirelesslytransmitted typically extends from about 10 to about 30 mm between thetransmitting and receiving antennas 18, 20. In this particular example,increasing the gap 84 to about 70 mm increases the range within whichelectrical energy is able to be wirelessly transmitted from about 30 mmto about 60 mm between the transmitting and receiving antennas 18, 20.In one or more embodiments modifying the gap 84 may change transferimpedance. As defined herein, “transfer impedance” is an electricalimpedance that is created by the current flowing within spaced aparttransmitting and receiving antennas. In general as the separationdistance between the transmitting and receiving antennas 18, 20decrease, transfer impedance increases. Transfer impedance is defined bythe following mathematical equation:

$\begin{matrix}{Z_{T}^{\prime} = \frac{\omega^{2}k^{2}L_{1}L_{2}}{R_{2} + {j\; \omega \; L_{2}} + Z_{2}}} & \;\end{matrix}$

where:

-   -   Z_(T)′ is the transfer impedance between the transmitting and        receiving antennas    -   k is the coupling between the transmitting and receiving        antennas    -   ω is the angular frequency    -   R₁ is the electrical resistance of the transmitting antenna    -   R₂ is the electrical resistance of the receiving antenna    -   L₁ is the inductance of the transmitting antenna    -   L₂ is the inductance of the receiving antenna    -   Z₂ is the electrical impedance of the electrical load of the        wireless transmission system

In one or more embodiments as the gap 84 approaches 0 mm, couplingbetween the transmitting antenna 18 positioned within the housing andthe receiving antenna 20, and coupling between the transmitting antenna18 and the repeater 32, both positioned within the base housing 24,increases. It is also noted that as the gap 84 approaches 0 mm, therange within which electrical energy is able to be transmitted generallydecreases because magnetic fields emanating from an antenna, such as arepeater 32 positioned about perpendicular to the transmitting antenna18 along the bottom housing sidewall 34 is relatively close to the planeof the transmitting antenna 18. In one or more embodiments, couplingbetween the transmitting antenna 18 and the repeater 32 within thehousing 24 of the transmitting base 16 is optimally between about 0.15to about 0.85. In one or more embodiments, the transmitting base 16 isconfigured such that the coupling between the transmitting antenna 18and the repeater 32 within the base housing 24 is enough such thatmagnetic fields generated by the transmitting antenna 18 are picked upand amplified by the repeater 32 so that the receiving antenna 20 canconvert the received magnetic fields into electrical current andvoltage. However, coupling between the transmitting antenna 18 and therepeater 32 within the transmitting base housing 24 should be of arelatively low value to maintain an acceptable transfer impedance suchthat the amplifier (not shown) of the receiving circuit (not shown) canoperate efficiently.

In one or more embodiments, as shown in FIG. 5, the outer edge 76 alongthe transmitter antenna outer perimeter 74 is in physical contact withthe interior surface of all the sidewalls that comprise the transmittingbase 16. As a result, the transmitting antenna 18 is capable oftransmitting magnetic waves and thus transmit wireless electrical powerfrom the transmitting base 16 about the entire circumference of the base16. Thus, wireless electrical power is capable of being transmittedabout a 360° radius around the transmitting base 16. Furthermore, sincethe transmitting antenna 18 is positioned in physical contact with theinterior surface 54 of the transmitting base housing 24 magnetic fieldstransmitted from the transmitting antenna 18 are capable of travelingfurther distances from the base 16. In one or more embodiments, thetransmitting antenna thickness 72 may range from about 0.2 mm to about 5mm. In an embodiment, the width of the transmitting antenna 18 may rangefrom about 20 mm to about 300 mm.

In one or more embodiments as illustrated in FIG. 5A, the transmittingantenna 18 may be positioned within the housing 24 of the transmittingbase 16 so that the magnetic field shielding material 70, such as theferrite material is positioned facing towards the wireless transmittingbase distal end 30 and the transmitting inductor coil 50 is positionedfacing towards the transmitting base proximal end 28. In thisembodiment, the shielding material 70 helps to direct the magneticfields emanating from the transmitting antenna 18 towards thetransmitting base proximal end 28. For example, such a configuration maybe used to help direct magnetic fields emanating from the transmittingantenna 18 through a surface, such a table supporting the transmittingbase 16 and an adjacently positioned electronic device 12 that isintended to be electrically charged or powered. Such a configurationthus allows for an increased amount of magnetic field emanating from thetransmitting antenna 18 to be received by the electric device 12configured with a receiving antenna 20. As a result, an increased amountof electrical energy is able to be wirelessly transferred between thetransmitting base 16 and the electronic device 12.

Furthermore, in one or more embodiments the wireless transmitting base16 may be constructed so that the transmitting inductor coil 50 of thetransmitting antenna 18 within the transmitting base 16 is positioneddirectly adjacent and facing an interior sidewall surface 54 of thetransmitting base housing 24. The magnetic field shielding material 70positioned distal the transmitting inductor coil 50 faces away from theinterior sidewall surface 54 and towards the interior of thetransmitting base 16. In one or more embodiments, the transmittingantenna 18 may be positioned within the housing 24 of the transmittingbase 16 so that the exterior surface of the transmitting inductor coil50 is in physical contact with the interior sidewall surface 54 of thetransmitting base housing 24. This embodiment allows for increasing themagnitude of the transmitted magnetic field. Therefore, as a result, thetransmission distance of the magnetic field and, thus, the wirelesselectric energy is increased. In one or more embodiments, thetransmission distance of the magnetic field 15 may be equal to aboutthree times the greater of the length 26, width 46, depth 48, ordiameter 58 of the transmitting base 16. In one or more embodiments, thetransmission distance of the magnetic field 15 may be equal to aboutfive times the greater of the length 26, width 46, depth 48, or diameter58 of the transmitting base 16.

In one or more embodiments, the magnetic field shielding material 70 maybe a ferrite material with a loss tangent as low as possible. In one ormore embodiments, the loss tangent of the ferrite material may be equalto or less than 0.70 at the antenna operating frequency. Such shieldingmaterials may include, but are not limited to, zinc comprising ferritematerials such as manganese-zinc, nickel-zinc, copper-zinc,magnesium-zinc, and combinations thereof. These and other ferritematerial formulations may be incorporated within a polymeric materialmatrix so as to form a flexible ferrite substrate. Examples of suchmaterials may include but are not limited to, FFSR and FFSX seriesferrite materials manufactured by Kitagawa Industries America, Inc. ofSan Jose, Calif. and Flux Field Directional RFIC material, manufacturedby 3M™ Corporation of Minneapolis, Minn. In one or more embodiments, thetransmitting antenna 18 incorporated with the shielding material 70,such as a ferrite material, should have a self-resonance frequency(SRF) >1.5 times the operating frequency, preferably an SRF >3 times theoperating frequency. For example, if the operating frequency is 6.78MHz, then the SRF of the antenna should be greater than 10 MHz.

Other desired properties of a ferrite shielding material include:

-   -   Real permeability (reflective of magnetic flux absorbing        capabilities), μ′: should be as HIGH as possible    -   Imaginary permeability (reflective of resistive loss), μ″:        should be as LOW as possible    -   Ratio: μ′/μ″: Should be as HIGH as possible    -   The Saturation flux density should be as high as possible. This        is an important factor especially when the system is operating        at relatively high power levels

In general, ferrite or other magnetic materials may be employed for thepurposes of increasing Mutual inductance between the transmitting andreceiving antennas 18, 20 and to magnetically insulate the metalliccomponents (e.g., PCB, battery) of a device from the magnetic fields ofthe wireless electrical energy transmitting system 14.

In one or more embodiments, the magnetic field shielding material 70 maycomprise a single sheet, or it may comprise a plurality of sheets ofmagnetic shielding material 70 having a gap positioned between themagnetic field shielding material and the inductor coil of the repeater32, the transmitting antenna 18, or the receiving antenna 20 to reduceeddy current losses within the respective antenna. Alternatively, themagnetic field shielding material 70 may be placed flush with theinductor coil of the repeater 32, the transmitting antenna 18, or thereceiving antenna 20. In one or more embodiments, the magnetic fieldshielding material 70 may comprise a magnetic material, a metallicmaterial, or a combination thereof.

In one or more embodiments, the receiving antenna 20 may be shieldedfrom surrounding electronic components within an electronic device 12 aswell as from a metal enclosure or enclosures that comprise theelectronic device 12. In one or more embodiments, a receiving inductorcoil 86 of the receiving antenna 20 may be shielded from surroundingelectronic components within an electronic device 12 as well as from ametal enclosure or enclosures that comprise the electronic device 12.The electronic components within an electronic device 12 may be shieldedfrom magnetic fields coupling with the receiving antenna 20. Forexample, shielding a receiving antenna 20 from a battery (not shown)placed directly behind the receiving antenna 20 within an electronicdevice 12. Magnetic fields may couple with the battery thereby inducingelectrical current in the battery and thus causing the battery to heatwhich may degrade the life of the battery. Other metallic parts of thedevice may need to be shielded from the antenna to prevent eddy currentsfrom being induced within the antenna and device which cause undesirableheating.

Thus, as will described in more detail, the embodiments of magneticfield shielding disclosed herein provide shielding of the transmittingand receiving antennas 18, 20 from such components as an electrochemicalcell (not shown) or other electronic components such that the qualityfactor of the antenna is sustained. Thus, the various magnetic fieldshielding embodiments provide for an increased quality factor andself-resonant frequency of the transmitting or receiving antennas 18,20. In addition, the magnetic field shielding embodiments provide forincreased coupling efficiency and end to end DC to DC efficiency.Furthermore, the magnetic field shielding embodiments provide forincreased power handling capability.

In one or more embodiments, the repeater 32, transmitting antenna 18 orreceiving antenna 18 may comprise at least one inductor coil such as thenon-limiting examples disclosed in U.S. Pat. App. Nos. 2017/0040690,2017/0040692, 2017/0040107, 2017/0040105, 2017/0040696, and 2017/0040688all to Peralta et al., 2017/0040691, 2017/0040694 to Singh et al.,2017/0040693 to Luzinski and 2017/0040695 to Rajagopalan et al., all ofwhich are assigned to the assignee of the present application andincorporated fully herein. In addition, the repeater 32, thetransmitting antenna 18 or the receiving antenna 20 may be configured ina multi-layer-multi-turn (MLMT) construction in which at least oneinsulator is positioned between a plurality of conductors. Non-limitingexamples of antennas having an MLMT construction that may beincorporated with the present disclosure may be found in U.S. Pat. Nos.8,610,530, 8,653,927, 8,680,960, 8,692,641, 8,692,642, 8,698,590,8,698,591, 8,707,546, 8,710,948, 8,803,649, 8,823,481, 8,823,482,8,855,786, 8,898,885, 9,208,942, 9,232,893, 9,300,046, all to Singh etal., and assigned to the assignee of the present application areincorporated fully herein. It is also noted that other antennas such as,but not limited to, an antenna configured to send and receive signals inthe UHF radio wave frequency such IEEE standard 802.15.1 may beincorporated within the present disclosure.

In one or more embodiments, the inductor coils of either the repeater,the transmitting antenna 18, or the receiving antenna 20 arestrategically positioned to facilitate reception and/or transmission ofwirelessly transferred electrical power or data through near fieldmagnetic induction. Antenna operating frequencies may comprise alloperating frequency ranges, examples of which may include, but are notlimited to, about 100 kHz to about 200 kHz (Qi interface standard), 100kHz to about 350 kHz (PMA interface standard), 6.78 MHz (Rezenceinterface standard), or alternatively at an operating frequency of aproprietary operating mode. In addition, the repeater 32 thetransmitting antenna 18 and/or the receiving antenna 20 of the presentdisclosure may be designed to transmit or receive, respectively, over awide range of operating frequencies on the order of about 1 kHz to about1 GHz or greater, in addition to the Qi and Rezence interfacesstandards. In addition, the repeater 32, the transmitting antenna 18 andthe receiving antenna 20 of the present disclosure may be configured totransmit and/or receive electrical power having a magnitude that rangesfrom about 100 mW to about 1,000 mW. In one or more embodiments thetransmitting inductor coil 50 of the transmitting antenna 18 isconfigured to resonate at a transmitting antenna resonant frequency orwithin a transmitting antenna resonant frequency band. In one or moreembodiments the transmitting antenna resonant frequency is at least 1kHz. In one or more embodiments the transmitting antenna resonantfrequency band extends from about 1 kHz to about 100 MHz. In one or moreembodiments the repeater inductor coil 98 of the repeater 32 isconfigured to resonate at a repeater resonant frequency or within arepeater resonant frequency band. In one or more embodiments therepeater resonant frequency is at least 1 kHz. In one or moreembodiments the repeater resonant frequency band extends from about 1kHz to about 100 MHz. In one or more embodiments the receiving inductorcoil 86 of the receiving antenna 20 is configured to resonate at areceiving antenna resonant frequency or within a receiving antennaresonant frequency band. In one or more embodiments the receivingantenna resonant frequency is at least 1 kHz. In one or more embodimentsthe receiving antenna resonant frequency band extends from about 1 kHzto about 100 MHz.

FIGS. 6-8 through illustrate one or more embodiments of variousconfigurations of the transmitting inductor coil 50 of the transmittingantenna 18. As shown in FIG. 6, the transmitting coil 50 may be of acurved shaped, such as of a semi-circle, a triangular shape as shown inFIG. 7 or a rectangular shape as shown in FIG. 8. In one or moreembodiments the transmitting inductor coil 50 may be configured in avariety of unlimited shapes. Such shapes are particularly designed toconform to the shape of the interior surface of the housing 24 of thetransmitting base 16.

FIGS. 9 and 9A illustrate one or more embodiments in which thetransmitting inductor coil 50 is positioned in contact with the interiorsidewall surface 54 of the housing 24 of the wireless transmitting base16. As shown in FIGS. 9 and 9A, the transmitting inductor coil 50 ispositioned in physical contact with the interior surface 54 of the rightsidewall 44. FIG. 9A illustrates the transmitting coil 50 positioned onthe interior sidewall surface 54. In one or more embodiments, as shown,the transmitting inductor coil 50 may be positioned so that it ispositioned to be co-planar with the interior surface 54 of thetransmitting base sidewall. In the embodiment shown, the transmittinginductor coil 50 is positioned about co-planar with the interior surface54 of the left sidewall 42 and about perpendicular to the interiorsurface of the bottom sidewall 34 at the base proximal end 28. In one ormore embodiments, the gap 84 is shown extending from the interiorsurface 54 of the bottom sidewall 34 at the proximal end 28 to thesurface of the transmitting antenna 18 that faces towards thetransmitting base proximal end 28.

FIGS. 10 and 11 illustrate one or more embodiments in which thetransmitting inductor coil 50 is shaped to conform to the interiorsurface of the transmitting base housing sidewall. As illustrated inFIG. 10, the transmitting inductor coil 50 is configured in arectangular shape. As illustrated in FIG. 11, the transmitting inductorcoil 50 is configured having a curved shape. In one or more embodimentsthe various configurations of the transmitting inductor coil 50 shown inFIGS. 10 and 11 show how the shape of the transmitting inductor coil 50is designed to conform to the shape of the sidewall of the housing 24 ofthe wireless transmitting base 16. For example, the rectangular shapedtransmitting inductor coil 50 illustrated in FIG. 10 is shown positionedon the interior surface of a transmitting base housing 24 having arectangular shaped sidewall. The curved shaped transmitting inductorcoil 50 illustrated in FIG. 11 is shown positioned on the interiorsurface of a transmitting base housing 24 having a curved shapedsidewall.

FIGS. 12 and 12A illustrate one or more embodiments in which thewireless transmitting base 16 may comprise multiple transmittingantennas 18 within its housing 24. As shown, the transmitting base 16comprises a first transmitting antenna 88 positioned along the interiorsurface of the bottom sidewall 34 at the transmitting base proximal end28 and a second transmitting antenna 90 positioned along the interiorsurface of the right sidewall 44 of the transmitting base 16. As shown,the transmitting inductor coil 50 of each of the first and secondtransmitting antennas 88, 90 is positioned in physical contact with theinterior surface of their respective housing sidewalls. In one or moreembodiments the magnetic field shielding material 70 may be positionedbehind and in contact with the transmitting inductor coil 50 of eitheror both of the first and second transmitting antennas 88, 90. In one ormore embodiments the first and second transmitting antennas 88, 90 maybe electrically connected to the transmitting electronic circuit 22 suchthat the respective first and second transmitting antennas 88, 90 may beindividually controlled. In addition, in one or more embodiments thefirst and second transmitting antennas 88, 90 may be electricallyconnected to the transmitting electronic circuit 22 so that electricalenergy may be wirelessly transmitted simultaneously or individually fromthe first and second transmitting antennas 88, 90. In one or moreembodiments the transmitting electronic circuit 22 may control theselection and/or operation of a repeater 32. FIG. 12 illustrates one ormore embodiments in which multiple electronic devices 12 aresimultaneously charged by positioning them adjacent to the wirelesstransmitting base 16. As shown in FIG. 12, a first electronic device 92is being charged by the first transmitting antenna 88 and a secondelectronic device 94 is being charged by the second transmitting antenna90. It is contemplated that the wireless transmitting base 16 is notlimited to two transmitting antennas 18. In one or more embodimentsmultiple transmitting antennas 18 and/or repeaters 32 may be positionedalong the interior surface of any sidewall within the transmitting basehousing 24. Thus, by configuring the wireless transmitting base 16 withmultiple repeaters 32 and/or transmitting antennas 18, the area ofwireless electrical energy transmission can be extended about thetransmitting base 16. Furthermore, since each of the multitude ofrepeaters 32 and/or transmitting antennas 18 can be individuallycontrolled, the transmission of electrical energy can be tuned orsteered in a particular direction or area segment.

FIG. 13 illustrates one or more embodiments of a block diagram of thetransmitting electronic circuit 22 comprising at least one repeater 32.As shown in the block diagram of FIG. 13, the external power supply 61is electrically connected to the transmitting electronic circuit 22(shown in the embodiments of FIG. 3 or 4) comprising at least onetransmitting antenna 18. As illustrated in FIG. 13, three repeaters 32are positioned away from the transmitting antenna 18. In the embodiment,each repeater 32 comprises a capacitor 96 that is electrically connectedto a repeater inductor coil 98.

FIG. 14 illustrates one or more embodiments in which the at least onerepeater 32 is positioned along the interior surface 54 of the wirelesstransmitting base housing 24. As shown, two repeaters 32 are positionedalong the interior surface of the left and right sidewalls 42, 44respectively of the transmitting base housing 24. The transmittingantenna 18 is positioned along the bottom sidewall 34 at the baseproximal end 28. In one or more embodiments the transmitting antenna 18wirelessly transmits electrical energy and/or data by emitting magneticfields. The two repeaters 32 each receive the wirelessly transmittedelectrical energy through the magnetic fields and further transmit theelectrical energy by emitting magnetic fields from their respectiverepeater inductor coil 98.

FIGS. 15 and 16 illustrate one or more embodiments of a flexibletransmitting antenna 100. In one or more embodiments the flexibletransmitting antenna 100 is designed to conform to the interior surfaceof the housing 24 of the wireless transmitting base 16. As shown, theflexible transmitting antenna 100 comprises at least one transmittinginductor coil 50 positioned on or within a substrate 102 that ismechanically flexible. In one or more embodiments, the substrate 102 iscomposed of a material such as a polymer that is capable of mechanicalbending or stretching. In one or more embodiments, the substrate 102 maybe composed of a composite material comprising a polymer, a ceramic, aglass, a metal, or a combination thereof. The polymeric material mayinclude polydimethylsiloxanes (PDMS), polyethyleneterephthalate (PET),Teflon, Teflon doped with a dielectric material, polytetrafluoroethylene(PTFE), ethylenetetrafluoroethylene (ETFE), parylenes, polyether blockamide (PEBAX), polyetheretherketone (PEEK), polystyrenes, polysulfones,polypropylenes, polycarbonates, polyvinyl chloride (PVC), polyxylylenepolymers, polyamides, polyimides, nylon, epoxies, and other suchsuitable polymers, elastomers and gels, including combinations thereof.Ceramic materials may include alumina (or aluminum oxide), bariumtitanate, zirconia-based ceramics such as YSZ (yttria-stabilizedzirconia), alumina based composites, glass ceramics such asalumina-silica, and the like.

Additionally, these ceramic materials may be used in conjunction withflexible polymer materials to create hybrid receiving/transmittingantennas, components, resonators, and subassemblies.

In addition, the substrate 102 is constructed of a relatively thinthickness that helps enable the flexibility of the substrate 102. In oneor more embodiments, the thickness of the substrate 102 may range fromabout 0.01 cm to about 0.5 cm. In one or more embodiments, the flexiblemechanical properties enable the transmitting antenna 100 to conform tothe interior surface or surfaces within the wireless transmitting base16. For example, the flexible transmitting antenna 100 may be positionedalong a curved surface within the transmitting base 16 or may bepositioned along and/or over a junction of two sidewalls of thetransmitting base housing 24.

FIG. 17 illustrates a graph that shows magnetic field strength as afunction of distance from a transmitting antenna 18. As shown, as themagnetic field travels in opposite directions from the transmittingantenna 18, the strength of the magnetic field decreases. Asillustrated, the magnetic field travels away from the transmittingantenna in opposing directions having an initial maximum magnitude. Forexample, as illustrated in FIG. 17, in front and in back of thetransmitting antenna 18. The magnetic field travels to a distance awayfrom the transmitting antenna 18 at which the magnitude of the fielddecays to zero. Thus, in one or more embodiments, in order to increasethe magnitude and distance of travel of the magnetic field, the magneticshielding material 70 is utilized. Thus, by shielding the magnetic fieldfrom one side of the antenna, the magnitude and direction of travel ofthe magnetic field can be increased in one direction.

FIG. 18 illustrates one or more embodiments of the construction of thetransmitting antenna 18 that may be used within the transmitting base 16of the present invention. As shown in the embodiment, the transmittingantenna 18 comprises a transmitting inductor coil 50 positioned proximalto the magnetic field shielding material 70. A conductive material 104,such as a sheet of copper, may be positioned distal the magnetic fieldshielding material 70. In one or more embodiments, the inclusion of theconductive material 104 within the antenna construction minimizeselectromagnetic interference (EMI). Thus, the transmitting antenna 18comprises a composite structure in which the magnetic shielding material70 is sandwiched between the transmitting inductor coil 50 and theconductive material 104. In one or more embodiments, a first gap 106 mayreside between the transmitting inductor coil 50 and the magnetic fieldshielding material 70. In one or more embodiments, a second gap 108 mayreside between the magnetic field shielding material 70 and theconductive material 104. In one or more embodiments, the first andsecond gaps 106, 108 may range from about 0 mm to about 10 mm. In afurther embodiment, the transmitting inductor coil 50 may be positionedon a substrate 110 such that the substrate 110 is positioned between thetransmitting inductor coil 50 and the magnetic field shielding material70. In one or more embodiments, the transmitting inductor coil 50 mayhave a transmitting inductor coil thickness 112 that ranges from about0.1 mm to about 2 mm. In one or more embodiments, the magnetic fieldshielding material 70 may have a magnetic field shielding materialthickness 114 that ranges from about 0.1 to about 3 mm. In one or moreembodiments, the conductive material 104 may have a conductive materialthickness 116 that ranges from about 0.05 mm to about 0.5 mm. In one ormore embodiments, the conductive material may comprise an electricallyconductive material, non-limiting examples include, but are not limitedto copper, nickel, aluminum, or a combination thereof.

Thus, by constructing the transmitting antenna 18 having at least one ofthe magnetic field shielding material 70 and the conductive material104, the emanating magnetic field is restricted from traveling intoundesired areas. In one or more embodiments, constructing thetransmitting antenna 18 having at least one of the magnetic fieldshielding material 70 and the conductive material 104, ensures that theemanating magnetic field travels in one direction, away from themagnetic field shielding material 70 and/or the conductive material 104thereby increasing the efficiency of the transmitting antenna 18. As aresult, magnetic fields and thus wireless electrical energy travelfurther distances before the magnitude of the magnetic fields decays tozero. As a result, the transmitting base 16 of the present invention iscapable of wirelessly transmitting an increased amount of electricalenergy and transmit the electrical energy further away from the base 16thereby enabling multiple electronic devices 12 to be charged orelectrically powered at distances away from the wireless transmittingbase 16.

FIGS. 19 and 19A illustrate one or more embodiments of the transmittingantenna 18 positioned along an interior surface of the housing 24 at thetransmitting base proximal end 28 in relation to a receiving antenna 20positioned within an electronic device 12. As shown in FIG. 19, bypositioning the transmitting antenna 18 comprising a transmittinginductor coil 50 in contact with the interior surface of the housingsidewall at the proximal end 28 and having magnetic field shieldingmaterial 70 positioned distal the transmitting inductor coil 50,magnetic fields emanate in a proximal direction from the transmittingantenna 18 through the base proximal end 28. Thus, emanating magneticfields that facilitate wireless transmission of electrical energy arepositioned closer to an electronic device 12 equipped with a receivingantenna 20 positioned on the same supporting surface as the transmittingbase 16, such as a table or desk. As a result, the magnitude of theemanating magnetic fields and thus the magnitude of wirelesslytransmitted electrical energy is increased about the base proximal end28 which electronic devices 12 to be charged or powered are typicallypositioned. In the embodiment illustrated in FIG. 19A, magnetic fieldsthat are shown emanating from the transmitting antenna 18 through thebase proximal end 28 are received by an electronic device 12 equippedwith a receiving antenna 20 positioned adjacent to the transmitting baseproximal end 28. Therefore, wireless electrical energy and/or data istransmitted more efficiently. In one or more embodiments, as illustratedin FIG. 19A, the transmitting inductor coil 50 and the receivinginductor coil 86 are positioned so that they are coplanar to each other.This orientation helps facilitate efficient wireless electrical energytransfer between the wireless transmitting base 16 and an electronicdevice 12 that is positioned adjacent to the wireless transmitting base16.

Alternatively, as illustrated in FIG. 20 in one or more embodiments, thetransmitting antenna 18 may be positioned within the housing 24 of thewireless transmitting base 16 such that the magnetic field shieldingmaterial 70 is in physical contact with the interior surface of at leastone housing sidewall. Furthermore, it is contemplated that thetransmitting antenna 18 may be positioned within the housing 24 of thewireless transmitting base 16 such that the conductive material 104 isin physical contact with an interior surface of at least one housingsidewall. In one or more embodiments, the wireless transmitting base 16may be constructed having a variety of transmitting antennas 20 and/orrepeaters 32 therewithin. These transmitting antennas 20 and/orrepeaters 32 may be positioned in a variety of unlimited orientations tomanipulate the direction and magnitude of the emanating magnetic fieldsthat enable wireless transmission of electrical energy and/or data.

FIG. 21 illustrates one or more embodiments of a transmitting antenna 18comprising a transmitting inductor coil 50 positioned on a magneticfield shielding material 70, such as a ferrite material. FIG. 21Aillustrates a cross-sectional view of the antenna shown in FIG. 21. Asillustrated, a sheet of conductive material 104 is positioned distal andin contact with the magnetic field shielding material 70.

FIG. 22. Illustrates one or more embodiments of a transmitting orreceiving antenna 18, 20 having a flexible connection 118 connecting therespective inductor coil 50, 86 with the conductive material 104. Asshown, the magnetic field shielding material 70 is positionedtherebetween. This embodiment thus allows for a flexible connectionbetween the inductor coil 50, 86 and the conductive material 104 withinthe respective transmitting or receiving antenna 18, 20.

FIGS. 23 and 24 illustrate one or more embodiments in which the magneticfield shielding material 70 comprises a plurality of separate panes 120of magnetic field shielding material. As shown, the plurality ofmagnetic field shielding panes 120 are positioned behind the inductorcoil 50, 86 of the antenna such as the transmitting or receiving antenna18, 20. In one or more embodiments, the plurality of magnetic fieldshielding panes 120 are positioned such that they are co-planar withrespect to each other. In addition, in one or more embodiments, amagnetic field shielding gap 122 may be positioned between adjacentpanes 120 of the shielding material 70. In an embodiment, the magneticfield shielding gap 122 may range from about 0.1 mm to about 10.0 mm. Inone or more embodiments, constructing the transmitting or receivingantenna 18, 20 having a plurality of magnetic field shielding materialpanes 120 with the gap 122 therebetween increases the quality factor,self-resonant frequency (SRF) and decreases the effective seriesresistance (ESR) of the respective antenna 18, 20. In one or moreembodiments, each pane 120 may have a pane length 124 that ranges fromabout 20 mm to about 40 mm, and a pane width 126 oriented aboutperpendicular to the pane length 124 that ranges from about 10 mm toabout 25 mm.

FIGS. 25A-25C illustrate one or more embodiments of variousconfigurations of a transmitting or receiving antenna 18, 20 configuredwith the magnetic field shielding material 70 and conductive material104. As shown, in the example of FIG. 25A, the antenna 18, 20 comprisesan inductor coil 50, 86 positioned on a substrate 110. Example ofsubstrates may include but are not limited to an insulating materialsuch as FR4, a polymeric material, or a ceramic material. FIG. 25Billustrates an embodiment in which the magnetic field shielding material70, such as FFSX is positioned in contact with the substrate 110 of therespective transmitting or receiving antenna 18, 20. FIG. 25Cillustrates an embodiment of the respective transmitting or receivingantenna 18, 20 comprising the magnetic field shielding material 70 andthe conductive material 104. As shown, a layer of the conductivematerial 104 comprising copper is positioned in physical contact withthe magnetic field shielding material 70 such that the shieldingmaterial is sandwiched between the inductor coil 50, 86 and theconductive material 104. The combination of the shielding material 70and the conductive material 104 thus provides a magnetic field shieldingstructure that minimizes travel of undesirable magnetic fields, therebyimproving the overall efficiency of the transmitting or receivingantenna 18, 20 and thus, the wireless electrical energy transmittingsystem 14 of the present application.

In one or more embodiments, various electrical performance parameters ofthe wireless electrical energy transmitting system 14 of the presentapplication were measured. One electrical parameter is quality factor(Q) defined below.

The quality factor of a coil defined as:

$Q = \frac{\omega*L}{R}$

Where:

-   -   Q is the quality factor of the coil    -   L is the inductance of the coil    -   ω is the operating frequency of the coil in radians/s.        Alternatively, the operating frequency (Hz) may be ω divided by        2π    -   R is the equivalent series resistance at the operating frequency

Another performance parameter is resistance of receiving antennaefficiency (RCE) which is coil to coil efficiency. RCE is defined as:

${R\; C\; E} = \frac{k^{2}*Q_{Rx}*Q_{Tx}}{\left( {1 + \sqrt{\left( {1 + {k^{2}*Q_{rx}*Q_{tx}}} \right)}} \right)^{2}}$

Where:

-   -   RCE is the coil to coil efficiency of the system    -   k is the coupling of the system    -   Q_(rx) is the quality factor of the receiver    -   Q_(tx) is the quality factor of the transmitter

Another performance parameter is mutual induction (M). “M” is the mutualinductance between two opposing inductor coils of a transmitting andreceiving antenna, respectively. Mutual induction (M) is defined as:

$M = \frac{V_{induced}}{j*\omega*I_{Tx}}$

Where:

-   -   V_(induced) is induced voltage on the receiver coil    -   I_(tx) is the AC current flowing through the transmitter coil    -   ω is the operating frequency multiplied by 2π

Mutual inductance can be calculated by the following relationship:

M=k*√{square root over (L _(Tx) *L _(Rx))}

Where:

-   -   M is the mutual inductance of the system    -   k is the coupling of the system    -   L_(Tx) is the inductance of the transmitter coil    -   L_(Rx) is the inductance of the receiver coil

TABLE I Mutual Conf. Inductance ESR Quality SRF Inductance No. (μH) (Ω)Factor (MHz) (nH) RCE (%) 1 1.94 1.0 82 55.19 510 77 2 1.9 0.83 98.571.3 516 78 3 1.98 0.90 94.3 66.8 — —

Table I above details various measured performance parameters of an NFMCsystem comprising a transmitting antenna 18 and a receiving antenna 20.The transmitting antenna 18 comprising an NC-2B Airfuel certifiedresonant transmitting inductor coil was used in the performance testingas detailed in configurations 1-3 of Table I. The transmitting antenna18 was configured having an inductor coil with a length of 170 mm and awidth of 100 mm and 6 turns. The receiving antenna 20 comprised areceiving inductor coil 86 having 5 number of turns. The receivinginductor coil 86 was configured having a length of 55 mm and a width of48 mm. Test configuration 1 comprised the receiving antenna 20 with thereceiving inductor coil 86 positioned on a single sheet of FFSX ferritematerial having a length of 55 mm and a width of 43 mm and a thicknessof 0.3 mm. The receiving antenna 20 in test configuration 1 furthercomprised an aluminum sheet having a thickness of 0.5 mm positionedbehind the ferrite shielding material. Test configuration 2 comprisedthe receiving antenna 20 with the receiving inductor coil 86 ofconfiguration 1 positioned on a plurality of 4 spaced apart ferritematerial panes 120. Each pane was constructed having a length of 26.5mm, a width of 22.5 mm, and a thickness of 0.3 mm. The receiving antenna20 was constructed such that a magnetic field shielding gap 122 of about3.0 mm extended between each pane 120. The receiving antenna 20 in testconfiguration 2 further comprised an aluminum sheet having a thicknessof 0.1 mm positioned behind the panes 120 of ferrite shielding material.Test configuration 3 comprised the receiving antenna 20 with thereceiving inductor coil 86 of configuration 1 positioned on a pluralityof 4 spaced apart ferrite material panes 120. Each pane 120 wasconstructed having a length of 26.5 mm, a width of 22.5 mm, and athickness of 0.3 mm. The receiving antenna 20 was constructed having amagnetic field shielding gap 122 of about 2.0 mm extending between eachpane 120 of magnetic field shielding material 70. The receiving antenna20 in test configuration 3 further comprised an aluminum sheet having athickness of 0.1 mm positioned behind the panes 120 of ferrite shieldingmaterial. As detailed in Table I shown above, constructing the receivingantenna 20 having a plurality of separate panes 120 of magnetic fieldshielding material 70 increased the quality factor, self-resonantfrequency, and resonator coupling efficiency (RCE). In one or moreembodiments, constructing the receiving antenna 20 having a plurality ofseparate panes 120 of magnetic field shielding material 70 decreaseseddy current circulation within the antenna which improves electricalperformance. Eddy currents are generally known in the art to causeundesirable heat and degrade the inductive properties of a coil antennawhich lead to a decreased wireless power transfer efficiency. It isnoted that the symbol “-” indicates that a measurement was not taken.

TABLE II Receiving Antenna Transmitting Antenna Attenuation ofAttenuation of Mutual Inductance Mutual Inductance Configuration No.(dB) (dB) 1 0.8 11.05 2 2.24 11.05 3 2.7 11.88 4 5.62 13.82

Table II above details various measured performance parameters of anNFMC system operating at 13.56 MHz comprising a transmitting antenna 18and a receiving antenna 20. The transmitting antenna 18 was configuredhaving an inductor coil with a length of 5 cm and a width of 5 cm and 4turns. The receiving antenna 20 comprised a receiving inductor coil 86having 4 number of turns. The receiving inductor coil 86 was configuredhaving a length of 5 cm and a width of 5 cm. The receiving antenna 20was positioned about 4 cm from the transmitting antenna 18. A conductivemetal sheet composed of aluminum was positioned between the transmittinginductor coil 50 and a transmitting pick up loop 128 (FIG. 26). The pickup loop 128 comprised 2 number of turns having a length of 40 mm and awidth of 40 mm. The metal sheet which comprised a length of 5.2 cm awidth of 5.2 cm and a thickness of 0.1 mm. An embodiment of the testconfiguration for the results shown in Table II is provided in FIG. 26.

Test configuration 1 comprised the conductive metal sheet beingpositioned at about 2 cm from the transmitting inductor coil 50. Testconfiguration 2 comprised the conductive metal sheet positioned about 1cm from the transmitting inductor coil 50. Test configuration 3comprised the conductive metal sheet positioned about 0.75 mm from thetransmitting inductor coil. Test configuration 4 comprised theconductive metal sheet positioned about 0.5 cm from the transmittinginductor coil 50. As detailed in Table II, test configuration 1 in whichthe conductive metal sheet was placed about 2 cm from the transmittinginductor coil exhibited the lowest attenuation at the receiving antennaat about 0.8 dB. Test configuration 4 in which the conductive metalsheet was placed about 0.5 cm from the transmitting coil exhibited thegreatest attenuation of 13.82 dB at the pick up loop. The resultsdetailed in Table II illustrate that the conductive metal sheet is aneffective shield of magnetic fields, however incorporating the metalshield in this example reduced the Mutual inductance between thetransmitting and receiving antennas 18, 20. Furthermore, the resultsdetailed in Table II illustrate how coupling efficiency is optimized bythe positioning of the magnetic field shielding material 70,particularly in the embodiments shown in FIGS. 5A and 12A. In one ormore embodiments, one should take into consideration the location ofelectrically conductive material and objects in the vicinity of thetransmitting or receiving antenna 18, 20 and the intended direction ofthe magnetic field when positioning the magnetic field shieldingmaterial 70 with respect to the transmitting or receiving inductor coil50, 86. For example, in the embodiment shown in FIG. 5A, since theintended direction of the emanating magnetic fields from thetransmitting inductor coil 50 is in the proximal direction, i.e.,through a supporting surface, and the transmitting antenna 18 within thetransmitting base 16 is constructed with the magnetic field shieldingmaterial 70 distal the transmitting coil 50 to shield the transmittingantenna 18 from various conductive materials such as circuit boards andelectrochemical cells positioned within the transmitting base 16 anddistal the transmitting antenna 18. In one or more embodiments, thevarious conductive materials such as circuit boards and electrochemicalcells may be positioned distal and in contact with the transmittingantenna 18, thus the magnetic field shielding material 70 is positionedtherebetween. In addition, in the embodiment shown in 12A, the magneticfield shielding material 70 is positioned on the proximal side of thetransmitting coil 50 since the intended direction of the magnetic fieldis in a distal direction through the transmitting base 16. In theexample shown in FIG. 12A, while magnetic field shielding material 70 isnot positioned between the transmitting inductor coil 50 and anelectrically conductive object, the boost of the repeater 32 is largeenough that coupling between the transmitting antenna 18 and therepeater 32 is increased.

TABLE III Config. M (μH) K M (μH) K M (μH) K No. 3 mm 3 mm 5 mm 5 mm 7mm 7 mm 1 0.109 0.22 0.0717 0.1445 0.049 0.098 2 0.124 0.23 0.07900.1488 0.0536 0.101 3 0.113 0.217 0.0736 0.1410 0.0524 0.100

Table III above details measured Mutual inductance (M) and antennacoupling coefficient (k) performance parameters of an NFMC systemcomprising a transmitting antenna 18 and a receiving antenna 20 at threeseparation distances, 3 mm, 5 mm and 7 mm. The transmitting antenna 18comprising a transmitting inductor coil 50 supported on a substratecomposed of FR4 was used in the performance testing as detailed inconfigurations 1-3 shown in Table III. The transmitting antenna 18 wasconfigured having an inductor coil with a length of 60 mm and a width of9.5 mm and 5 turns. The receiving antenna 20 comprised a receivinginductor coil 86 having 2 number of turns supported on a substratecomprising FR4. The receiving inductor coil 86 was configured having alength of 60 mm and a width of 6 mm.

Test configuration 1 comprised the receiving antenna configured with thereceiving coil supported on the substrate comprising FR4. Testconfiguration 2 comprised the receiving antenna constructed with thereceiving coil positioned directly in contact with FFSX3 ferritematerial configured having the same dimensions as the receiving inductorcoil 86. The ferrite material had a thickness of about 0.3 mm. Testconfiguration 3 comprised test configuration 2 with the addition of asheet of copper metal positioned in contact with the ferrite material.In test configuration 3, the ferrite material was sandwiched between thereceiving inductor coil and the copper metal sheet. The copper metalsheet had a thickness of about 0.1 mm.

As detailed in Table III, the addition of the ferrite material with thereceiving antenna 20 improved Mutual induction in comparison to testconfiguration 1 comprising only the receiving inductor coil 86. Inaddition, as shown by the experimental results, detailed in Table III,the addition of the copper sheet generally degrades Mutual inductance.

TABLE IV Inductance Electrical Configuration No. (μH) Resistance (Ω)Quality Factor 1 - Transmitting 1.292 1.01 80.37 Antenna 2 -Transmitting 1.524 1.18 81.15 Antenna 3 - Transmitting 1.4127 1.33 66.74Antenna 4 - Receiving 0.189 0.121 94.99 Antenna 5 - Receiving 0.2070.178 99.03 Antenna 6 - Receiving 0.199 0.19 89.19 Antenna

Table IV above details the electrical performance factors of inductance,electrical resistance, and quality factor of embodiments of transmittingand receiving antennas at a measured frequency of 10 MHz in variousconfigurations. The transmitting antenna 18 comprised a transmittinginductor coil 50 configured having a length of 5 cm, a width of 5 cm and4 turns. The receiving antenna 20 comprised a receiving inductor coil 86having a length of 5 cm, a width of 5 cm, and 4 number of turns.

Test configuration 1 comprised only the transmitting coil. Testconfiguration 2 comprised the transmitting coil in contact with theFFSX3 ferrite material. The ferrite material having a thickness of about0.3 mm. Test configuration 3 comprised test configuration 2 with theaddition of an aluminum metal sheet that was positioned in contact withthe ferrite material. Test configuration 3 comprised the ferritematerial positioned between the transmitting inductor coil 50 and thealuminum metal sheet. The aluminum metal sheet had a thickness of about0.1 mm.

Test configuration 4 comprised only the receiving inductor coil 81246.Test configuration 5 comprised the receiving inductor coil 86 in contactwith FFSX3 ferrite material. The ferrite material had a thickness ofabout 0.3 mm. Test configuration 6 comprised test configuration 5 withthe addition of an aluminum metal sheet that was positioned in contactwith the ferrite material. Test configuration 6 comprised the ferritematerial positioned between the receiving coil and the aluminum metalsheet. The aluminum metal sheet had a thickness of about 0.1 mm.

As detailed in Table IV above, the inductance and electrical resistanceof both the transmitting and receiving antennas 18, 20 increased withthe addition of the ferrite material. It was also observed that theinductance increased at a greater rate than the electrical resistance atthe measured frequency of 10 MHz. This resulted in an increase in thequality factor when the ferrite material was added to the antennastructure. It was also observed that the addition of the copper metalsheet degraded the quality factor.

TABLE V Receiver V_(loop) (V) at V_(loop) (V) at V_(loop) (V) at Config.No. 3 mm 5 mm 7 mm 1 0.482 0.555 0.525 2 0.39 0.411 — 3 0.212 0.22 —

Table V above details the induced voltage in which a one-turn loopantenna comprising a length of 1.6 cm and a width of 0.9 cm positionedabout 1.5 mm from the receiving inductor coil 86 was used to detect theefficiency of the shielding of the receiving antenna 20. An NFMC systemcomprising a transmitting antenna 18 and a receiving antenna 20 at threeseparation distances, 3 mm, 5 mm and 7 mm were utilized for theexperiment.

The transmitting antenna 18 used in the performance testing as detailedin configurations 1-3 shown in Table V comprised a resonant transmittinginductor coil 50 supported on a substrate comprising FR4. Thetransmitting inductor coil 50 had a length of 5 cm and a width of 5 cmand 4 turns. The receiving antenna 20 comprised a receiving inductorcoil 86 supported on a substrate comprising FR4. The receiving inductorcoil was configured having a length of 5 cm, a width of 5 cm, and 4turns.

Test configuration 1 comprised only the receiving antenna 20 comprisingthe receiving inductor coil 86 supported on the FR4 substrate. Testconfiguration 2 comprised the FR4 substrate in contact with FFSX3ferrite material. The ferrite material having a thickness of about 0.3mm. Test configuration 3 comprised test configuration 2 with theaddition of a copper metal sheet that was positioned in contact with theferrite material. Test configuration 3 comprised the ferrite materialpositioned between the receiving inductor coil 86 and the copper metalsheet. The copper metal sheet had a thickness of about 0.5 mm.

The results in Table V indicate that for about the same amount ofcurrent in a DC load, the induced voltage in the loop dropped about 19%by adding the ferrite to the receiving coil, and dropped about 56% whenthe copper metal sheet and ferrite were added to the receiving coil. Itis noted that the symbol “-” indicates that a measurement was not taken.

TABLE VI Inductance Config. No. (μH) Resistance (Ω) Quality Factor 10.205 0.196 89.07 2 0.198 0.201 83.89

Table VI above details the inductance, electrical resistance and qualityfactor measurements of embodiments of a receiving antenna 20 that waselectrically connected to a cellular phone. The transmitting antenna 18comprised a transmitting inductor coil 50 configured having a length of60 mm, a width of 9.5 mm and 5 turns. The receiving antenna 20 compriseda receiving inductor coil 86 having a length of 60 mm cm, a width of 6mm, and 2 number of turns.

Test configuration 1 comprised the receiving coil in contact with FFSXferrite material. The ferrite material having a thickness of about 0.3mm. Test configuration 2 comprised test configuration 2 with theaddition of an aluminum metal sheet that was positioned in contact withthe ferrite material. Test configuration 2 comprised the ferritematerial positioned between the receiving coil and the copper metalsheet. The aluminum metal sheet had a thickness of about 0.1 mm.

It was observed that adding the cellular phone to the receiving inductorcoil 86 and ferrite configuration degraded the quality factor by about10 percent. In addition, adding the cellular phone to the receiving coil86, ferrite and copper metal sheet configuration degraded the qualityfactor by about 6 percent.

It is noted that in one or more embodiments, a high inductance inductorcoil may be required to achieve sufficient wireless transmission ofelectrical energy. For example, in instances where the distance betweenthe transmitting antenna 18 and the receiving antenna 20 is relativelylarge, i.e., greater than about half the length of the transmittingantenna, or the respective transmitting and receiving antennas 18, 20are not oriented directly facing each. Furthermore, when the respectivetransmitting and receiving antennas 18, 20 are oriented such that theyare tilted, shifted, or rotated with respect to each other a highinductance inductor coil may be required to achieve sufficient wirelesstransmission of electrical energy. It is noted that coupling isgenerally at a maximum when the respective transmitting and receivingantennas 18, 20 are directly facing each other.

In one or more embodiments, as a first-order approximation, the voltageinduced in the receiving inductor coil 50 due to current flowing in atransmitting antenna 20 is about proportional to the number of turns ofthe transmitting inductor coil 50 of the transmitting antenna (N_(TX)),the amount of current flowing through the transmitting antenna (I_(TX)),and the number of turns of the receiving inductor coil (N_(RX)). Thus,the induced voltage can be calculated using the following equation:V_(induced)=f (N_(TX)×N_(RX)×I_(TX)). Furthermore, in this embodiment,it is assumed that N_(RX) is fixed and is not a design variable. Inaddition, in this example, it is assumed that I_(tx) is maximized andthe N_(TX)×I_(TX) product is not capable of inducing a sufficientvoltage on the receiving inductor coil. Therefore, in one or moreembodiments, to increase induced voltage in the receiving antenna 20,the number of turns of the transmitting inductor coil 50 of thetransmitting antenna (N_(TX)) should be increased.

It is generally noted that as the number of turns of the transmitting orreceiving antenna 18, 20 is increased, the self-resonant frequency (SRF)of the respective antenna structure typically becomes too small for theamount of current in the coil to be assumed as quasi-static. In otherwords, the phase difference of the current becomes too large. Inaddition, other spurious effects may include the respective transmittingor receiving antenna 18, 20 becoming increasingly sensitive and lossy inthe presence of extraneous objects, such as a metallic object. Inaddition, a high inductance may result due to the large number of turnsof the inductor coil. This, therefore requires the addition of acapacitance for tuning the inductance of the respective transmitting orreceiving antenna 18, 20, particularly at the operating frequency. It isfurther noted that the required capacitance value required to tune theinductance may be of the order of the parasitic capacitance of therespective inductor coil.

Therefore, in one or more embodiments, capacitive components may beintroduced within the transmitting and/or receiving antenna 18, 20 inorder to achieve the required number of inductor coil turns whilereducing sensitivity of the antenna to electrical loads and the presenceof metallic objects. Thus, relatively small inductor coils 50, 86 may beconnected in series with capacitors 96. In one or more embodiments, theinductor coils 50, 86 may be connected in series with capacitors 96 thatare electrically connected within a circuit such as a printed circuitboard (PCB) or flexible circuit board (FCB).

In one or more embodiments surface mount capacitors may be soldered on aPCB or FCB. Alternatively, to surface mount capacitors, a parallel platecapacitor 130 and/or an unt capacitor 132 may be fabricated on or withinthe PCB or FPC to impart a desired capacitance to the transmitting orreceiving antenna 18, 20. FIG. 27 illustrates examples of a parallelplate capacitor 130 and an interdigitated capacitor 132. The benefit ofutilizing a parallel plate capacitor 130 or an interdigitated capacitor132 configuration is that they provide a robust thinner design that isgenerally of a lower cost.

In one or more embodiments, the parallel plate capacitor 130, as shownin FIG. 27, comprises a dielectric material 134 positioned between twoopposing electrically conducting plates 136 positioned in parallel toeach other.

Non-limiting examples of an interdigitated capacitor 132 are shown inFIGS. 27 and 28A-28C. In one or more embodiments, as illustrated inFIGS. 27 and 28A-28C interdigitated capacitors 132 typically have afinger-like shape. In one or more embodiments, the interdigitatedcapacitor 132 comprises a plurality of micro-strip lines 138 thatproduce high pass characteristics. The value of the capacitance producedby the interdigitated capacitor 132 generally depends on variousconstruction parameters. These include, a length 140 of the micro-stripline 138, a width 142 of the micro-strip line 138, a horizontal gap 144between two adjacent micro-strip lines 138, and a vertical gap 146between two adjacent micro-strip lines 138 (FIG. 28A). In one or moreembodiments, the length 140 and width 142 of the micro-strip line 138can be from about 10 mm to about 600 mm, the horizontal gap 144 can bebetween about 0.1 mm to about 100 mm, and the vertical gap 146 can bebetween about 0.0001 mm to about 2 mm.

In one or more embodiments, the inter-digitated capacitor 132 can beintegrated within a substrate 110 such as a PCB shown in FIG. 29. In thecross-sectional view of the embodiment shown FIG. 29, an insulativematerial 148 of the PCB, such as FR4 is positioned between a firstinterdigitated capacitor 150 and a second interdigitated capacitor 152.In addition, magnetic field shielding material 70, such as a ferritematerial may also be incorporated within the structure. As shown in theembodiment of FIG. 29 the ferrite layer comprises the bottom layer ofthe respective structure. Thus, the interdigitated capacitor 132provides a means to add capacitance to the transmitting or the receivingantenna 18, 20 in a small compact design. In one or more embodiments,the transmitting or receiving inductor coil 50, 86 may be positioned onthe surface of the interdigitated capacitor 132. Alternatively, thetransmitting or receiving inductor coil 50, 86 may be positionedsurrounding the interdigitated capacitor 132. In one or moreembodiments, the interdigitated capacitor 132 may be positioned withinan opening or cavity within the substrate 110 supporting thetransmitting or receiving inductor coil 50, 86. In one or moreembodiments, the interdigitated capacitor 132 provides a cost-effectivemeans to add capacitance to an inductor coil 50, 86. In addition, theinterdigitated capacitor 132 is mechanically durable and may be used toconnect a tuned inductor coil 50, 86 directly to a circuit board. In oneor more embodiments, interdigitated capacitors 132 can also be useful inapplications where relatively thin form factors are preferred. Forexample, in the embodiment shown in FIG. 12A, the repeater inductor coil98 is positioned along an outer edge of the transmitting base 16. Inthis embodiment, an interdigitated capacitors 132 may be used to tunethe repeater inductor coil 98 in lieu of a surface mount capacitorbecause of the mechanical robustness, relatively thin design, andreduced cost of the interdigitated capacitor 132. For similar reasons,an interdigitated capacitor 132 can be used to tune a transmitting orreceiving inductor coil 50, 86.

Prior art magnetically coupled transmitting antennas cannot wirelesslytransmit electrical energy over long distance, typically on the order ofabout 0 mm to about 60 mm. Generally, for increased wirelesstransmission distances, the inductance of the antenna is increased toachieve target coupling required to induce a desired voltage within thereceiving inductor coil 86 of the receiving antenna 20. Increasing theinductance of the transmitting inductor coil 50 however, typically leadsto a decrease in the self-resonance frequency (SRF) of the transmittingantenna 18. Thus, if the inductance is too high, the SRF of thetransmitting antenna 18 may be reduced, for example, less thanapproximately four times the operating frequency, which may lead toincreased sensitivity of the transmitting inductor coil 50 to variationsin electrical load and the presence of metallic objects. In addition, ifthe inductance of the transmitting antenna 18 is too high, theequivalent series resistance (ESR) of the transmitting antenna 18 at theoperating frequency, may result in reduced efficiency of the transfer ofwireless electrical energy. In one or more embodiments, interdigitatedcapacitors 132 are not only useful for tuning the transmitting inductorcoil 50 and/or the receiving inductor coil 86 but can also be used tominimize sensitivity of the respective coil 50, 86 between coil traces.In this embodiment, shifts in current phase are created by theinterdigitated capacitor 132 itself without the need for additionalelectronic components. In one or more embodiments, interdigitatedcapacitors 132 can be used in lieu of surface mount capacitors to tunetransmitting and receiving inductor coils 50, 86 as well as forminimizing sensitivity of respective transmitting and receiving inductorcoils 50, 86 to metallic surfaces that may be positioned in the vicinityof the coil.

In one or more embodiments, the inventive concepts of the presentapplication outlined herein enable the design of the transmittingantenna 18 that is capable of transmitting wireless electrical energyand data over increased distances at relatively low amounts oftransmitting antenna current (ITx) while maintaining a relatively lowinductance. Thus, the wireless electrical energy transmitting system 14of the present application is more efficient and less sensitive tovariations in electrical loads and the presence of metallic objects. Thewireless electrical energy transmitting system 14 of the presentapplication, therefore, comprises a transmitting antenna 18 havingincreased self-resonant frequencies, an increased quality factor and anincreased receiving coupling efficiency (RCE).

In one or more embodiments, capacitance such as lumped capacitiveelements 154 (FIG. 30C) may be electrically connected to thetransmitting inductor coil 50, receiving inductor coil 86, or repeaterinductor coil 98 to reduce reflected impedance of the respectiveantenna. In one or more embodiments, lumped capacitive elements 154 maybe electrically connected between traces of the transmitting, receiving,or repeater inductor coils 50, 86, 98. Or alternatively, in one or moreembodiments, lumped capacitive elements 154 may also be electricallyconnected between inductor coils 50, 86, 98 of the respective antenna,both embodiments reduce the overall electrical impedance of the antenna18, 20, or the repeater 32. Thus, as a result, the inductor coil 50, 86,98 becomes less sensitive to changes in electrical load and the presenceof metallic objects.

It is noted that antennas with low inductance and low coupling generallyrequire higher current from an amplifier (not shown) to feed therequired electrical power. High inductance/coupling designs, requiringless current are characterized by a relatively large impedance shift,high ESR, and low SRF.

An example of such a high inductance/coupling transmitting antenna 18 isa “High Range” AIR-Fuel transmitter. In one or more embodiments, a “HighRange” AIR-Fuel transmitter is a transmitting antenna 18 configured towirelessly transmit electrical energy in a “z-axis” direction over atransmission distance of between about 25 mm to about 40 mm. Such “HighRange” AIR-Fuel transmitters require inductances, on the order ofbetween about 8 pH to about 12 pH, to achieve target coupling over the“z-axis” transmission distance.

In one or more embodiments, the transmitting or receiving inductor coil50, 86 is configured having an increased number of turns that increasethe inductance of the respective inductor coil. As inductance of thetransmitting or receiving coil 50, 86 increases, the inductor coil'sself-resonant frequency approaches the operating frequency. Furthermore,the electrical impedance of the inductor coil may change in the presenceof metallic surfaces and non-conductive bodies having a relativepermittivity greater than 1. Thus, the presence of metallic surfacesand/or non-conductive bodies having a relative permittivity greater than1 may lead to detuning of the respective inductor coil 50, 86 and/or adecrease in the efficiency of the transmission of wireless electricalenergy. In addition, this condition may result in an increasedtemperature of either or both the transmitting and receiving antennas18, 20, which may potentially damage the power amplifier or otherantenna circuitry.

In one or more embodiments, capacitors 96, such as lumped capacitiveelements 154, a parallel plate capacitor 130, an interdigitatedcapacitor 132, a surface mount capacitor (not shown), or a combinationthereof may be used to minimize de-tuning and potentially over heatingof the transmitting antenna 18, receiving antenna 20, or repeater 32. Inone or more embodiments, capacitors 96, such as lumped capacitiveelements 154, a parallel plate capacitor 130, an interdigitatedcapacitor 132, a surface mount capacitor (not shown), or a combinationthereof are electrically connected at appropriate locations on therespective transmitting inductor coil 50, receiving inductor coil 86 orrepeater inductor coil 98 to decrease electrical impedance of therespective inductor coil. As a result, the inductance of the respectivecoil is increased which increases coupling between either of thetransmitting antenna 18, the receiving antenna 20, the repeater 32, andcombinations thereof, particularly over relatively large transmissiondistances on the order of about 30 mm. In addition, the distributedcapacitors help to reduce phase difference across the length of therespective inductor coil 50, 86, 98. Reduction of phase differencesresults in a more even electrical current distribution which reducesimpedance shift and decreases the impedance of the respectivetransmitting antenna 18, receiving antenna 20 or repeater 32. It isnoted that the transmitting inductor coil 50 most efficiently transferselectrical power when it is perfectly tuned. Impedance shifts aregenerally due to the presence of metallic objects that couple with thetransmitting inductor coil 50. The presence of a metallic object maychange the imaginary impedance of the transmitting inductor coil 50,which generally results in the de-tuning of the wireless electricalenergy transmitting system 14.

As illustrated in FIG. 30C, a lumped capacitive element 154 is added toa transmitting or receiving antenna 18, 20 which is represented by theelectrically connected inductors 156 and resistors 158. In one or moreembodiments, the electrical circuit illustrated in FIG. 30A represents atransmitting or receiving antenna 18, 20 configured without a capacitor.As shown in the circuit of FIG. 30A, the transmitting or receivingantenna 18, 20 is represented by the inductor 156. The configurationshown in FIG. 30A is identified as D-pF. FIG. 30B illustrates anelectrical circuit embodiment of a transmitting or receiving antenna 18,20 comprising electrically connected inductors 156 and resistors 158.

TABLE VII Capacitance Inductance Antenna (pF) (μH) ESR (Ω) SRF (MHz)D∞pF n/a 20.02 6.00 20.71 D680pF 680 17.92 5.04 21.57 D200pF 200 13.544.01 21.60 D96pF 96 7.44 3.40 21.70 D68pf 68 3.14 3.70 22.60

Table VII shown above details the measured inductance, equivalent seriesresistance (ESR) and self-resonant frequency (SRF) of various receivingantennas 20 configured with capacitors 96 having various capacitances.In the experiment, a receiving antenna 20 comprising a receivinginductor coil 86 having a length of 100 mm and a width of 100 mm with 12turns was used. In the configurations listed in Table VII, shown above,two capacitors, each having the capacitance as detailed in the secondcolumn of Table VII were electrically connected to the receiving antenna20. For example, the receiving antenna identified as D200 pF wasconfigured with two capacitors, each having a capacitance of 200 pF thatwere electrically connected to the receiving inductor coil 86. It isnoted that the receiving antenna identified as D-pF was not configuredwith a capacitor and therefore only comprised the receiving inductorcoil 86.

As shown in Table VII, adding capacitors 96 to the receiving coil 86reduced impedance shifts, increased resonator coupling efficiency andlowered the sensitivity of the receiving inductor coil 86 by decreasingthe electrical impedance of the receiving antenna 20. As detailed inTable VII above, receiving antenna D-pF that was not configured with acapacitor, exhibited the greatest inductance, ESR, and lowest SRF. Incontrast, receiving antenna D68 pf, which comprised two 68 pFcapacitors, exhibited the lowest inductance, a reduced ESR and increasedSRF. This electrical performance can be explained because as capacitancedecreases, imaginary impedance increases. As a result, the overallimpedance of the receiving inductor coil 86 decreases, and the inductorcoil becomes closer to in phase, thus SRF and ESR are reduced.

In one or more embodiments, the inductance of the transmitting inductorcoil 50, the receiving inductor coil 86 and the repeater inductor coil98, may be reduced by electrically connecting lumped capacitors 154along the length of the respective inductor coil 50, 86, 98. If, forexample, the inductance is reduced to 4 μH from 16 μH the impedancevariation comes out to be between [−21j to 13j], a variation of 34j,which is equivalent to an inductance of 0.8 μH. In one or moreembodiments, the efficiency of the wireless transmission of electricalenergy is increased by tuning the transmitting and receiving inductorcoils 50, 86 to a specific operating frequency using capacitance that iselectrically connected to the inductor coil. In the embodiment disclosedabove, an inductor coil 50, 86 having an inductance of about 4 μHgenerally requires a tuning capacitance of between about 400 pf to about600 pf. An inductor coil 50, 86 with an inductance of about 16 μHgenerally requires a tuning capacitance of between about 50 pF to 150pF. It is noted however that using a tuning capacitance of a relativelylow value may reduce the transmission distance of the transmittingantenna 18 as the tolerance of the tuning capacitance may de-tune theantenna. Furthermore, an inductor coil 50, 86 with an increasedinductance of 16 μH typically generates a magnetic field having anincreased magnitude which could undesirably couple with a metallicobject. As a result, the impedance sensitivity of the inductor coil 50,86 may increase. Thus, for these reasons outlined in this example, it isbeneficial to reduce the inductance of the inductor coil 50, 86 usingthe addition of lumped capacitive elements 154 and/or surface mountcapacitors to tailor the inductance of the inductor coil 50, 86 thatutilizes an optimal tuning capacitance.

TABLE VIII Transmitting Antenna Capacitance Quality Impedance Config(pF) Factor RCE (%) M (nH) Shift (Ω) D∞pF N/A 85.97 79.57% 652 −65jD680pF 680 112.65 81.02% 630 −60j D200pF 200 151.82 83.63% 584 −52jD96pF 96 205.42 85.58% 526 −38j D68pF 68 185.66 84.90% 501 −31j

Table VIII summaries the measured values of quality factor, coil-to-coilefficiency (RCE), Mutual inductance and impedance shift for variousantenna configurations. In this experiment, coil-to-coil efficiency(RCE), Mutual inductance (M), and impedance shift measurements wereperformed using an RIT3-1 certified Resonator Interface Tester (RIT)from AIR-FUEL Rezence specification. The instrument is intended tosimulate impedance shift, coupling and voltage range of a cellular phoneantenna with an embedded wireless power resonator. The RIT3-1 devicecomprises an inductor coil having a length of 78 mm and a width of 52 mmthat is supported by a magnetic field shielding material comprisingPanasonic's KNZNCR ferrite material having a thickness of 0.7 mm. Duringthe testing, the RIT3-1 instrument was electrically connected to variouscapacitors having a capacitance as detailed in the “Capacitance” columnof Table VIII.

Various antenna electrical performance parameters including qualityfactor, coil-to-coil efficiency (RCE), Mutual inductance (M), andimpedance shift were measured with the RIT3-1 instrument connected tocapacitors having various capacitance values as detailed in Table VIII.It is noted that configuration D-pF did not comprise a capacitor. In oneor more embodiments, coil-to-coil efficiency (RCE) was calculated byderiving the optimal efficiency at an optimal electrical load on thereceiving antenna. Mutual Inductance was measured directly fromscattering parameters (S-parameters) that summarize the electricalparameters of the 2 port network that comprised the transmitting andreceiving inductor coils.

It is noted that the D96 pF antenna, as detailed in Table VIII above,measured the highest quality factor. This correlates with Impedanceanalyzer measurements that also showed the D96 pF antenna having thelowest ESR (Table VII) and also increased RCE measurement where itmeasured a significant improvement of 6.01% over the D0 pF antenna. TheD-pF antenna measured the highest Mutual Inductance at about 650 nHwhich decreased by about 24% to 500 nH with the D68 pF antenna.

FIGS. 31 and 32, compare the efficiency curves of the D0 pF and D96 pFantennas, respectively. As shown, the z-axis is the coil to coilefficiency in percent of the respective D0 pF and D96 pF antennas. TheX-axis is the imaginary electrical impedance due to the metallicsurfaces of the cellular phone enclosure that was in contact with thereceiving antenna and the R axis is the real impedance which isattributed to the electrochemical cell of the cellular phone in ohms. Asillustrated in FIGS. 31 and 32, the added capacitance of the D96 pFantenna shifted the maximum inductance from an imaginary impedance ofabout 0 ohms (X-axis) and a real impedance of about 0 ohms (R axis) to areal impedance of about 5 ohms (R axis) and an imaginary impedance ofabout 0 ohms (X-axis). It is noted that the antenna configuration of D96pF shown in FIG. 32 is preferred because the antenna configurationexhibited increased coil to coil efficiency over a larger x=axis andr-axis spectrum.

Thus, it is contemplated that the wireless electrical energy transfersystem of the present disclosure is capable of being configured having avariety of receiving and transmitting antenna configurations.Furthermore, such a configuration of the variety of antennas allows forand significantly improves the wireless transmission of electricalenergy and/or data across significantly increased distances such thatelectronic devices can be electrically charged or powered by positioningthem a distance away from the source of wireless electrical energy. Itis further contemplated that the various magnetic shielding materials 70can be strategically positioned adjacent to the transmitting orreceiving antennas 18, 20 to enhance quality factor and Mutualinductance between adjacently positioned transmitting and receivingantennas 18, 20. It is appreciated that various modifications to theinventive concepts described herein may be apparent to those of ordinaryskill in the art without departing from the spirit and scope of thepresent disclosure as defined by the appended claims.

As used herein, the phrase “at least one of” preceding a series ofitems, with the term “and” or “or” to separate any of the items,modifies the list as a whole, rather than each member of the list (i.e.,each item). The phrase “at least one of” does not require selection ofat least one of each item listed; rather, the phrase allows a meaningthat includes at least one of any one of the items, and/or at least oneof any combination of the items, and/or at least one of each of theitems. By way of example, the phrases “at least one of A, B, and C” or“at least one of A, B, or C” each refer to only A, only B, or only C;any combination of A, B, and C; and/or at least one of each of A, B, andC.

The predicate words “configured to”, “operable to”, and “programmed to”do not imply any particular tangible or intangible modification of asubject, but, rather, are intended to be used interchangeably. In one ormore embodiments, a processor configured to monitor and control anoperation or a component may also mean the processor being programmed tomonitor and control the operation or the processor being operable tomonitor and control the operation. Likewise, a processor configured toexecute code can be construed as a processor programmed to execute codeor operable to execute code.

A phrase such as “an aspect” does not imply that such aspect isessential to the subject technology or that such aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations.An aspect may provide one or more examples of the disclosure. A phrasesuch as an “aspect” may refer to one or more aspects and vice versa. Aphrase such as an “embodiment” does not imply that such embodiment isessential to the subject technology or that such embodiment applies toall configurations of the subject technology. A disclosure relating toan embodiment may apply to all embodiments, or one or more embodiments.An embodiment may provide one or more examples of the disclosure. Aphrase such an “embodiment” may refer to one or more embodiments andvice versa. A phrase such as a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurations,or one or more configurations. A configuration may provide one or moreexamples of the disclosure. A phrase such as a “configuration” may referto one or more configurations and vice versa.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” or as an “example” is not necessarily to be construed aspreferred or advantageous over other embodiments. Furthermore, to theextent that the term “include,” “have,” or the like is used in thedescription or the claims, such term is intended to be inclusive in amanner similar to the term “comprise” as “comprise” is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “include,” “have,” or the like is used in the descriptionor the claims, such term is intended to be inclusive in a manner similarto the term “comprise” as “comprise” is interpreted when employed as atransitional word in a claim.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. No claim element is to be construedunder the provisions of 35 U.S.C. § 112, sixth paragraph, unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “stepfor.”

Reference to an element in the singular is not intended to mean “one andonly one” unless specifically so stated, but rather “one or more.”Unless specifically stated otherwise, the term “some” refers to one ormore. Pronouns in the masculine (e.g., his) include the feminine andneuter gender (e.g., her and its) and vice versa. Headings andsubheadings, if any, are used for convenience only and do not limit thesubject disclosure.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of particular implementations of the subject matter.Certain features that are described in this specification in the contextof separate embodiments can also be implemented in combination in asingle embodiment. Conversely, various features that are described inthe context of a single embodiment can also be implemented in multipleembodiments separately or in any suitable sub-combination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to a subcombination or variation of a sub combination.

What is claimed is:
 1. A method of operating a structure configured totransmit wireless electrical energy, the method comprising the followingsteps: a) connecting a transmitting base to an electrical power source,the transmitting base comprising: i) a housing having a sidewall with asidewall thickness that extends between opposing interior sidewallsurfaces, wherein the transmitting base extends from a base proximal endto a base distal end; ii) at least one transmitting antenna positionedwithin the transmitting base, the at least one transmitting antennacomprising a transmitting coil, wherein the transmitting coil ispositioned adjacent to the housing interior sidewall surface, andwherein the transmitting coil is configured to resonate at atransmitting antenna resonant frequency or a transmitting antennaresonant frequency band; and iii) a wireless transmitting circuitelectrically connected to the at least one transmitting antenna, whereinthe wireless transmitting circuit is configured to modify electricalenergy from an electrical source to be wirelessly transmitted by the atleast one transmitting antenna; and b) transmitting electrical energywirelessly from the transmitting base.
 2. The method of claim 1 whereinthe at least one transmitting antenna transmits the electrical energy byresonating at the transmitting antenna resonant frequency of at least 1kHz.
 3. The method of claim 1 wherein the at least one transmittingantenna transmits the electrical energy by resonating at thetransmitting antenna resonant frequency at about 1 kHz to about 100 MHzor within the transmitting antenna resonant frequency band that extendsfrom about 1 kHz to about 100 MHz.
 4. The method of claim 1 wherein theelectrical energy has a magnitude from about 100 mW to about 500 W. 5.The method of claim 1 wherein a capacitor is electrically connected tothe transmitting coil.
 6. The method of claim 5 wherein the capacitorcomprises a surface mount capacitor, a parallel plate capacitor, or aninterdigitated capacitor.
 7. The method of claim 1 wherein a magneticfield shielding material is positioned adjacent to the transmittingcoil.
 8. The method of claim 7 wherein the magnetic field shieldingmaterial is selected from the group consisting of a zinc comprisingferrite material, manganese-zinc, nickel-zinc, copper-zinc,magnesium-zinc, and combinations thereof.
 9. The method of claim 7wherein the magnetic field shielding material has a loss tangent lessthan about 0.70.
 10. The method of claim 7 wherein a space separates thetransmitting coil from the magnetic field shielding material.
 11. Themethod of claim 7 wherein a conductive material is positioned adjacentto the magnetic field shielding material.
 12. The method of claim 1wherein the transmitting coil of the at least one transmitting antennais positioned having a gap between the interior sidewall surface and thetransmitting coil.
 13. The method of claim 1 wherein the transmittingcoil of the at least one transmitting antenna is positioned in physicalcontact with the interior sidewall surface.
 14. The method of claim 1wherein a gap extends between the at least one transmitting antenna anda bottom sidewall that resides at the base proximal end.
 15. The methodof claim 14 wherein the gap is equal to or less than 10 cm.
 16. Themethod of claim 1 wherein the wireless transmitting circuit comprises atransmitting selection sub-circuit.
 17. The method of claim 1 whereinthe transmitting coil is adjacent to or in contact with a substrate,wherein the substrate is flexible.